Thanos Petsos (; born 5 June 1991) is a Greek professional footballer who plays as a defensive midfielder for Latvian club Riga. Club career Early career Petsos started his football career at the age of eight for Düsseldorf 99 SC. In 2001, he was lured away to professional club Bayer Leverkusen. He progressed through the youth system and was part of the team that finished runner-up in the Under 19 Bundesliga in 2010. He made his debut for the Leverkusen reserve team in March 2010. He made seven more appearances in the 2009–10 season while continuing to play for the under-19 team. He made his Bundesliga debut on 24 April 2010 against Hannover 96. With a Leverkusen contract running until 2014, Petsos was loaned out to 1. FC Kaiserslautern for one season in 2010. He made his full Bundesliga debut for the club on 13 November 2010 against VfB Stuttgart being played as a right back. In April 2011, it was announced his loan to Kaiserslautern would be extended for the following 2011–2012 season. He made a total of 42 appearances for the club. Greuther Fürth In 2012, Petsos signed for newly promoted SpVgg Greuther Fürth on a three-year deal. He made his debut for the club on 18 August 2012 in a DFB-Pokal match against Kickers Offenbach, he then went on to make his Bundesliga debut on 31 August 2012 against Mainz 05. He went on to make a total of 15 appearances for the club. Rapid Wien On 15 July 2013, Petsos joined Austrian Bundesliga club Rapid Wien on a three-year agreement. He made his debut for the club on 27 July 2013 against Wiener Neustadt. On 3 May 2015, in a 2–2 draw away to SK Sturm Graz he scored for 2–1 with a hard long-range shot. On 4 August 2015, he greatly contributed to 3–2 away win with a strong performance in the third qualifying round of the 2015–16 UEFA Champions League against Ajax. In early September, he suffered an injury during training with the Greece national team keeping him out of action for several weeks. Rapid in October stated their intention to extend Petsos' contract after he had been one of the team's best players during its strong start to the season. On 18 October 2015 he returned to the team, starting in an Austrian championship game against Wolfsberger AC, but suffered an injury in